Impact of COVID-19 Pandemic on Completion of Radiation Therapy After Lumpectomy for Early-Stage Breast Cancer.

[BACKGROUND] Whole-breast radiation therapy (RT) following lumpectomy has become a standard of care for early-stage breast cancer (ESBC) treatment. Hypofractionated RT (HFRT) has demonstrated equivalent oncologic efficacy to standard fractionation (SFRT). The COVID-19 pandemic accelerated adoption of shorter treatment regimens; however, its impact on RT completion rates and treatment equity has not been well-characterized.

[METHODS] Using the National Cancer Database, patients with ESBC who received post-lumpectomy RT from 2018 to 2022 were identified. SFRT was defined as 1.8-2.0 Gy per fraction and HFRT as 2.66-2.70 Gy per fraction. RT completion was defined as receipt of ≥ 46 Gy for SFRT and ≥ 40 Gy for HFRT. Pre-COVID (2018-2019) and post-COVID (2021-2022) RT completion and HFRT adoption rates were compared using chi-square tests. Adoption and completion were analyzed by race, ethnicity, income, and facility type.

[RESULTS] Among 25,658 patients (pre-COVID n = 13,381; post-COVID n = 12,277), HFRT use increased from 82.9% to 93.6%, while SFRT declined from 17.1% to 6.4% (P < .0001). Overall RT completion improved from 94.8% to 96.4% (P < .0001). HFRT completion rates remained higher than SFRT (pre-COVID: 97.2% HFRT vs. 83.1% SFRT; post-COVID: 97.5% vs. 80.5%). HFRT adoption increased across all racial and income groups (all P < .0001), with completion exceeding 96% across all subgroups. Racial and income disparities in HFRT differences decreased by a relative reduction of 53.3% and 40.5%, respectively.

[CONCLUSIONS] Post-COVID shifts toward HFRT were associated with higher RT completion and reduced disparities, suggesting more efficient and equitable treatment delivery of adjuvant breast RT.